SAFARI

POWER STEERING

2. Checking for oil leaks:

The control valve must fully activate in order to be

able to determine the leakage oil in the steering

system. For this reason a minimum of approx. 200 N

(20 kg) must be applied to the steering wheel. The

test is carried out with the pump running and a pressure

is set on the steering testing rig which lies

approximately 20 bar below the maximum pressure

given on the type plate.

The maximum permissible leakage oil under these

conditions is 8 LPM for type M 033.

The test can be carried out with blocked steering drop

arm or in the end position of the cylinder. Repeat the

leakage oil check at a pressure of 20 – 30 bar.

1. Checking the valve setting:

The pump is running and the oil circulates through the

hydraulic system of the steering unit. No counter force

is set on the steering input shaft on the steering test

rig. The torque measuring tool (Tool no. 4) is turned

slowly to both sides up to the stops in each case and

the device is released several times during this

process. The steering must not move in any direction

on its own.The difference in the torques when steering

to left and right must not exceed 30% in respect of

the low value up to a pressure of 3 bar compared with

the flow pressure when the steering drop arm is

blocked

2. Checking control valve:

Close the control valve by turning the steering wheel

then build up the maximum pump pressure. The

steering wheel should then be slowly released. The

valve should then return to the 0 position, i.e. the oil

pressure must fall to the flow pressure.

3. Checking the seals:

No leaks should be visible on the hydraulic steering

unit after running for 10 minutes in the neutral position

of the steering valve.

Tightness at high pressure must be determined during

the test in accordance with points 2 to 4 of this section.

Place the dust seal (1.1) on the segment shaft up to

the shoulder, applying HTR2 grease or equivalent

between the dust seal and housing, and place the

protective cap (70) on the steering spindle end,

applying HTR2 grease or equivalent between the

protective cap and valve housing.

X Fitting the steering unit in the vehicle

Note:

In order to ensure perfect functioning of the ZF hydraulic

ball & nut steering, special emphasis must be paid to

cleanliness when fitting all the relevant units of the

system and when laying the oil lines. In order that

faults can be avoided due to foreign bodies or dirt in

the oil steering circuit the cap plugs on the line

connections of the steering unit, oil pump, working

cylinder, valves etc. should only be removed when

connecting on the lines. Connection lines and securing

elements must be carefully cleaned and debarred.

1. Clean any paint or dirt from the contact faces of

the mounting brackets.

2. Insert the steering gear in the mounting bkts and

tighten the bolts with the corresponding torque.

3 Stresses which may occur during the assembly of

the steering gear/bearing block due to the position

of the dash board or on the circumstances when

securing the steering column tube and steering

spindle. Stresses can cause bending forces

especially in the steering spindle which, depending

on size and frequency, may lead to fractures or

impair the easy movement of the steering gear.

To check whether the steering unit has been installed

correctly should be carried out as follows:

3.1 Check the movement of the steering gear at the

mounting bracket, steering drop arm and drag links

(s).

Fit the universal joint or the flexible coupling between

the steering column and the steering gear.The angled

fork section must be at right angles to the markings

on the steering spindle and steering columns tube or

valve housing in straight ahead position. The angle

should be the same if two joints are used and the joint

forks must be arranged in one plane. If it is not possible

to fit them in this way, synchronization can be

achieved by positioning the forks on the serrated

gearing in respect of each other.

Hammer blows on the joints must be avoided in the

case of aluminium universal joints because this might

lead to destruction or stiffness. Connect them by